Gripper for doffing arrangements in spinning machines



March 2, 1965 s. ROLLER 3,171,631

GRIPPER FOR DOFFING ARRANGEMENTS IN SPINNING MACHINES Filed April 11,1963 4. i 1g 8 27 i 29 H I l .15 2

23 l 2 25 24 g 31 1| I 33 INVENTOR. \SIEGFRIED ROLLER A TTORNEYS UnitedStates Patent 3 1'71 6231 camera non norrrnd annarscuarnnrs IN SEINNENGMACHHNES Siegfried Roller, Feilbach, near Stuttgart, Germany,

assignor to Fir-ma C. Eugen Meier, Felibach, Stuttgart, Germany, aGerman firm Filed Apr. 11, 1963, Ser. No. 272,272 Claims priority,application Germany, Apr. 18, W62, Rd 52,5 57 9 Claims. (Cl. 294-67)This invention relates in general to article transporting chucks and, inparticular, to a new and useful fluid operated gripper, or chuck, fordrawing 0d or doffing arrangements at bobbin changers for spinningmachines.

The present invention has particular application to spinning machinesand particularly to a fluid pressure operated gripper, or chuck, forlifting and transporting articles such as for dofling arrangements atbobbin changers of spinning machines. In the more modern embodiments ofspinning machines, the dofling, or drawing oit, procedure takes placenot when the bobbin is at rest, but during the movement of the bobbinchanger. For this reason it is important to compensate for anymisalignment of the bobbin arrangement in any resultant movement.

In accordance with the invention, there is provided a pneumaticallyoperated gripper or chuck device which is supplied with air pressurethrough a movable hose, and which includes a gripper head which ismounted in the holding means in an articulated manner. The arrangementis such that the gripper head may be pivoted about its holding ormounting means in order to compensate for variations in the movement,and without affecting the dotting procedure.

In accordance with a preferred arrangement, the holding meansadvantageously includes an arm member having a bore which tapersinwardly in a downward direction. The gripper head is provided with aball extension which rides in the bore of the holding means, and theball is able to be pivoted on the tapered inner portion of the bore ofthe holding means. The arrangement advantageously includes a coverhaving a tapered interior wall to accommodate a small ball which rideson the bore defined in the ball-shaped member and is biased against thetapered interior of the cover. The upper small ball acts as a centeringmeans, which is urged upwardly against the center of the taper of thecover by a compression spring to cause the gripper head to be urged intoa central position in respect to the holding means.

The invention further includes a gripper head which includes a sleevemember which is inflatable under pres sure supplied from a pneumatichose connection for the purpose of gripping a bobbin. The spring, whichis biased against the centering ball, has its opposite end riding on aplunger which is reciprocable in the gripper head. The plunger has alower end movable in the interior of the sleeve member at a locationdirectly above the top of the bobbin which is grasped by the inflatablesleeve member. The engagement of the bobbin causes upward movement ofthe plunger and insures that the gripper head will be centered byincreasing the force of the biasing spring acting on the cover of theholding means. When the bobbin is released, the plunger moves downwardlyto aid in the ejection of the bobbin and, also, to permit easier pivotalmovement of the gripper head.

In accordance with a further feature of the invention, the gripper headis constructed with a central bore, which is threaded at the lower endto accommodate a hollow threaded screw member. The hollow screw memberis inserted as a centering element for accommodating a plunger member,which reciprocates in the gripper head and also provides means forsecuring an inflatable gripping element. The gripping element comprisesa sleeve of elastic material which is arranged so that one end is heldby the hollow screw member and the intermediate portion is directeddownwardly in a U-shape with the upper outer end being held on theexterior portion of the gripper head. The elastic material sleeve willeX- pand when supplied with a pressurized fluid, such as air, to engagea bobbin head when the gripper is operated.

Accordingly, it is an object of this invention to provide an improvedarticle holding and transporting device.

A further object of the invention is to provide a gripper for articles,such as bobbins, which include an inflatable element for engaging thebobbin, mounted within a gripper head in a location to receive pressurefrom a fluid pressure source.

A further object of the invention is to provide a pneumatic gripper fordrawing off, or dofling, arrangements at bobbin changers for spinningmachines which includes a gripper head connected with a movable airhose, and wherein the gripper head is mounted for articulated movementin respect to the holding means.

A further object of the invention is to provide a device such as agripper which is operated from a fluid pressure source supplied to ahead portion and wherein the head is swivelably mounted within a bore ofa holding arm.

A further object of the invention is to provide a gripper which issimple in design, rugged in construction and economical to manufacture.

The various features of novelty which characterize the invention arepointed out with particularity in the claims annexed to and forming apart of this specification. For a better understanding of the invention,its operating advantages and specific objects attained by its use,reference should be had to the accompanying drawing and descriptivematter in which there is illustrated and described a preferredembodiment of the invention.

In the drawing:

The only drawing in the case is a transverse section through a gripperhead and holding means constructed in accordance with the invention.

Referring to the drawing in particular, the invention embodied thereincomprises a gripper head generally designated 49 which is carried byholding means, partially indicated at 1. The holding means includes afree end which has a bore extending therethrough and which includes alower portion which is tapered in cone-shaped manner for the purpose ofswivelably supporting a ball member 4 of the gripper 4d. The top of thebore 2 is closed by a screw cover 5 which has a dish-shaped depressionor conical interior wall 5.

In accordance with the invention, the lower portion of the ball member 4is provided with a cylindrical extension which is threaded into a bore 9of a gripper head 8. The ball member 4 is provided with a bore 34 inwhich is positioned a compression spring 10. The upper end of thecompression spring It) bears on a centering ball 11, and the lower endbears on an annular flange 12 of a plunger 13.

The lower end of the bore 9 of the gripper 8 is threaded at 15 toreceive a hollow bolt element, or sleeve member 16. The plunger 13 isslidable in the bore of the sleeve member 16 and the lower movement ofthe plunger is limited by the abutment of the flange portion 12 againstthe top surface of the sleeve member 16.

A sleeve member or cylindrical gripper cover 13 is held to the lower endof the gripper head 8 by means of a threaded ring 17 which has aninwardly extending end portion which engages around an outwardlyextending upper end portion of the sleeve member to hold it against thegripper head. The lower end of the sleeve member 18 is provided with afrusto-conical portion which forms a guide for centering a bobbin 3t)within the sleeve 18 of the gripper th. V

The sleeve 18 accommodates an annular collar member or sleeve 2th ofelastic material, such as rubber, which is arranged within the sleeve ina bent condition forming a substantially U-shaped cross section with theintermediate portion arranged lowermost and supported on a curvedannular ledge 42, formed on the interior side of the guide portion 19 ofthe sleeve 18. The annular collar 20 is provided with an end having abead-like formation 21 which is held in a recess 22. formed between thegripper head 8 and the sleeve 18. The fitting of the parts is such thatthis connection is air-tight. The opposite end of the annular collar 26is provided with a bead portion 23 which is pressed by a flange 24 ofthe hollow sleeve 16 against an end face 26 of the gripper head 8. Awasher or packing material is inserted between the flange 24 and thehead portion 23 in order to form an air-tight connection at thislocation.

A movable air hose 27 is connected with the gripper head 8 into alaterally defined bore 23, which communicates with a longitudinal bore2% which, in turn, leads to the space defined between the inner andouter bends of the annular collar 29. When compressed air is suppliedthrough the hose 27, the annular collar member will expand, causing theinterior wall to move outwardly for engagement, for example, with thetop of the bobbin 39. The air may also be discharged out through thetubing 27 in this manner.

The gripper head 4% operates as follows:

The holding means 1, with the gripper head, is lowered onto. the bobbin3% and the upper end of, the bobbin is received within the opening 31formed by the annular sleeve or collar 20. The gripper head 3 may be deivered by swinging the ball 4 within the bore of the holding means 1 inorder to compensate for any inexactness of the bobbin arrangement andthe cone-like guide 19 facilitates directing the upper portion of thebobbin head into the space 31.

The top of the bobbin 3d presses against the plunger 13 when .thegripper head with the holding means is moved downwardly thereover andefiects upward movement as indicated by the arrow 32 to cause the spring10 to exert a stronger pressure on the centering ball 11. and thearresting of the gripper head in its position in a resilient manner. Theair hose 27 is then supplied with compressed air by means (not shown) sothat the inner portion 33 of the collar 26 is pressed against the bobbin30. The bobbin is thus held stationarily in the sleeve 18 and thegripper head 3.

' The holding means 1 then moves together with the gripper head 8 andthe bobbin upwardly, whereby the bobbin 30 is dotted or drawn olf. Inthe final position,

of the holding means 1, the release of the bobbin 3%) takes place byallowing the escape of the compressed air upwardly through the bore 29and outwardly through the bore 28. The ejection procedure is acceleratedby" the movement of the plunger 13 which moves rapidly, downwardly in adirection opposite to the arrow 32 tov insure positive ejection of thebobbin, 3t). Downward movement of the bobbin is effected by theexpansion of the spring 10, and this facilitates the movement of theball 4 of the head 8 in the bore 2 of the holding means, due tothe'relaXed force on the spring, i

While a specific embodiment of the invention has been shown anddescribed in detail to illustrate, the application of the inventiveprinciples, it will be understood that this from such principles.

What is claimed is:

1. A gripper for drawing off or doffing arrangements at bobbin changersfor spinning machines, comprising holding means, a gripper, meansmounting said gripper in said holding means in an articulated manner, afluid pressure supply hose for actuating said gripper connected to saidgripper in a manner to permit movement thereof, said means mounting saidgripper including a bore defined in said holding means having a taperedlower end, said gripper having a head portion with a ball member with abore defined therethrough pivotally movable on the tapered portion onthe bore of said holding means, a small ball positioned in the bore ofsaid ball member, a cover on the end of the bore of said holding meansopposite from the tapered portion and overlying said small ball, andmeans biasing said small ball against the cover.

2. A gripper according to claim 1, wherein said cover includes acone-shaped interior wall against which said small ball is biased.

3. A gripper according to claim 1, including a plunger reciprocable insaid head, said means biasing said ball including a compression springheld between said plunger and said ball, said plunger being engageableand movable upwardly by engagement of said head withlan article such asa bobbin to be lifted and movable downwardly under the urging of saidspring to eject the article.

4. A device for picking up and transporting articles such as a bobbinfor doiiing in a spinning machine and comprising a holding member havinga bore with a tapered lower interior surface, a gripper including a headportion having a central bore, a ball member having a bore definedtherethrough and connected to the upper end of said head portion andhaving a rounded exterior articulated within the bore of said holdingmember on the tapered lowerv surface thereof, a fluid pressure supplyhose connected to said head portion for supplying fluid under pressurefor operating said gripper, guide means carried at the lower end of saidhead for guiding and centering an article,

such as a bobbin, to be picked upin said gripper, expandable grippermeans carried Within said guide means and connected to said fluidpressure supply hose for receiving pressure therefrom for expanding saidgripper means into engagement with an article to be picked up and forholding the article, means associated with said ball member for urgingsaid ball member to a central position in respect to said holding meansincluding a small ball adjacent the top of the bore of said ball member,said holding means having a cover over said small ball, and spring meansin said ball member bore biasing said ball upwardly against said cover.7

5. A device according to claim 4, wherein said spring means includes aplunger reciprocable in said head, said spring means including acoil'spring abutting against one end of said plunger and against saidsmall ball, said plunger having an end portion extending downwardly tosaid guide means and being movable upwardly to compress said spring uponengagement of said gripper withan article such as a bobbin.

6. A device for picking up and transporting articles, such as bobbins,for dofling purposes in a spinning machine, comprising: a holding memberhaving a bore with the lowerportion of the bore being tapered inwardlyto form a conical ledge, a cover at the top of said bore, a gripperassembly including a .ball member having a central bore definedtherethrough and having an exterior ball portion engaged on the conicalsurface of the bore of said.

holding member for articulative movement thereon, a small ball membercarried on the upper end of the central bore of said ball member, acompression spring in the central bore of said ball member, a gripperhead connected to said ball member and having a bore in communicationwith the central bore thereof, a plunger slidable in the bore of saidgripper head and having a top portion abutting against said spring, saidspring urging said small ball against said cover, an annular collarmember of resilient material bent into a substantially U-shapedsectional configuration with an inner end disposed adjacent an end faceof said head with an outer end disposed adjacent a recess portion ofsaid head at a location spaced circumferentially outwardly from saidinner portion, a sleeve guide connected to the outer portion of saidhead and extending downwardly therefrom around said collar and having anopening at the lower face for guiding an article into the annular spacedefined by the interior wall of said collar member, means for sealingeach end of said annular collar member adjacent said head and hosemember connected to said head for supplying fluid pressure to saidannular collar member for inflating the same, and internal bores definedin said head member for communieating with said inflatable collar memberfor permitting fluid pressure to be directed between the walls thereoffor expanding the inner wall into engagement with an article Within saidguide sleeve.

7. A device according to claim 6, wherein the lower end of said plungermember is disposed in a space defined within said guide sleeve andwithin the interior wall of said collar member in a position to contactan article being inserted therein, said plunger being movable upwardlyto compress the spring against said small ball for urging said gripperinto a centered position.

References Cited by the Examiner UNITED STATES PATENTS 2,303,209 1/43Schrnntzer 29487 2,873,996 2/59 McHugh 294-90 2,962,856 12/60 Ingharn204- X FOREIGN PATENTS 364,156 1932 Great Britain.

SAMUEL F. COLEMAN, Primary Examiner. ERNEST A. FALLER, 111., Examiner.

1. A GRIPPER FOR DRAWING OFF OR DOFFING ARRANGEMENTS AT BOBBIN CHANGERSFOR SPINNING MACHINES, COMPRISING HOLDING MEANS, A GRIPPER, MEANSMOUNTING SAID GRIPPER IN SAID HOLDING MEANS IN AN ARTICULATED MANNER, AFLUID PRESSURE SUPPLY HOSE FOR ACTUATING SAID GRIPPER CONNECTED TO SAIDGRIPPER IN A MANNER TO PERMIT MOVEMENT THEREOF, SAID MEANS MOUNTING SAIDGRIPPER INCLUDING A BORE DEFINED IN SAID HOLDING MEANS HAVING A TAPEREDLOWER END, SAID GRIPPER HAVING A HEAD PORTION WITH A BALL MEMBER